bairdc
02-25-2005, 11:30 AM
Well, over the past week or so, I've migrated about half my network to OSPF from static routes. A couple of nights ago, I disabled all of the static routes except the default.
Now, I'm at the point where I should disable the static default routes, but I have to admit, I'm scared to death to do it. So far, in my experience, OSPF has proven to be "quirky" at best. Once it's running, it seems to run very well. However, right now my network is not having any problems. I have some serious doubts about OSPF's resilience when presented with some real-life network issues.
Basically, my fear stems from my experience in disabling static routes the other night. On at least two occasions, I disabled the static routes on a box, and then did the required "Activate Changes", only to find that a router two or three hops away suddenly had lost half of its OSPF-learned routes. In order to fix it, I had to log into the box having trouble (or one of its neighbors), and restart OSPF. The nasty thing there is that since all the static routes are gone, it's a bit more difficult to get access to a box if it loses its OSPF routes. It pretty much requires logging into a neighbor (assuming the neighbor still has its OSPF routes), and then SSH'ing from there to the affected box.
Anyway, If a simple "Activate Changes" on one box can break OSPF on another box up or downstream, then what is going to happen when a box reboots for some reason, or if a flakey wireless link causes a route to become unstable. I worry that instead of recalculating the routes on the fly and finding a route around the problem that OSPF will simply stop working on some routers, which will require me to log in to the affected routers, and restart OSPF. In other words, it will require me to babysit it. However, IMO, that's one of the reasons you run a routing protocol--so you don't have to babysit the network.
Anyway, as far as I can tell, I think I've followed all the guidelines posted by those who have had success (many thanks). All my wireless links are non-broadcast, with neighbors defined and I removed all the redistributes from each router. Like I said, OSPF seems to be very stable now, but then my network is currently very stable. I'm very nervous, however, about whether it will work as it should if any network instabilities are thrown into the mix.
I would love to have some input from those of you who have been running it for while. Have your OSPF implementations actually been faced with any network instabilites, and if so, how did it respond?
Craig
Now, I'm at the point where I should disable the static default routes, but I have to admit, I'm scared to death to do it. So far, in my experience, OSPF has proven to be "quirky" at best. Once it's running, it seems to run very well. However, right now my network is not having any problems. I have some serious doubts about OSPF's resilience when presented with some real-life network issues.
Basically, my fear stems from my experience in disabling static routes the other night. On at least two occasions, I disabled the static routes on a box, and then did the required "Activate Changes", only to find that a router two or three hops away suddenly had lost half of its OSPF-learned routes. In order to fix it, I had to log into the box having trouble (or one of its neighbors), and restart OSPF. The nasty thing there is that since all the static routes are gone, it's a bit more difficult to get access to a box if it loses its OSPF routes. It pretty much requires logging into a neighbor (assuming the neighbor still has its OSPF routes), and then SSH'ing from there to the affected box.
Anyway, If a simple "Activate Changes" on one box can break OSPF on another box up or downstream, then what is going to happen when a box reboots for some reason, or if a flakey wireless link causes a route to become unstable. I worry that instead of recalculating the routes on the fly and finding a route around the problem that OSPF will simply stop working on some routers, which will require me to log in to the affected routers, and restart OSPF. In other words, it will require me to babysit it. However, IMO, that's one of the reasons you run a routing protocol--so you don't have to babysit the network.
Anyway, as far as I can tell, I think I've followed all the guidelines posted by those who have had success (many thanks). All my wireless links are non-broadcast, with neighbors defined and I removed all the redistributes from each router. Like I said, OSPF seems to be very stable now, but then my network is currently very stable. I'm very nervous, however, about whether it will work as it should if any network instabilities are thrown into the mix.
I would love to have some input from those of you who have been running it for while. Have your OSPF implementations actually been faced with any network instabilites, and if so, how did it respond?
Craig